Liquid-level indicator



March 16 1926, 1,576,512

M. B. JACKSON vLIQUID LE'IVEL INDICATOR Filed Oct. 9, 1923 Patented Mar,16, 192.6.

UNITE srarss MAUNSELL B. JACKSON, OF TORONTO, ONTARIO, CANADA, ASSIGNOR'IO HIMSELF, ED-

WARD MCMAHON, AND THOMAS CAMERON BATE, BOTH' 0F OTTAWA, ONTARIO,

CANADA, TRUSTEES.

LIQUID-LEVEL INDICATOR.

' Application led October 9, 1923. Serial No. 667,485.

To all whom t may concern:

Be it known that l, MAUNsnLL Bownus J'AoKsoN, oi' ythe city of Toronto,in the county oi York, Province of Ontario, Canada, a subject of theKing of Great Britain, have invented certain new and useful Improvementsin Liquid-Level indicators, ot' which the following is a specification.

This invention relates to apparatus for indicating when the liquid levelin a tank falls below a predetermined minimum and more particularly toVapparatus of this type used in connection with a vacuum feed system forinternal combustion engines and my object is to provide simple apparatusthat-may be manufactured cheaply and that may be readily installed inexisting vacuum leed systems without Adanger of forming any air leakstherein.

I attain my object by means et the constructions hereinafter describedand illustrated in the accompanying drawings in whicl Fig. l is a crosssection of my indicator showing its connection with a vacuum eed system;y

Fig. 2 a front elevation of the indicator partly broken away to show theinterior thereof;

Fig. 3 a similar view to Fig. 2 showing the movable parts of theindicator in their normal position; and

Fig. 4 a diagrammatical View of the indicator.l y

l is a supply tank oi a vacuum supply system commonly used inautomobiles and well known in the art. The system also includes a.supply pipe line 2 leading from the supply tank to a vacuum tank (notshown) which is connected with the intake pipe or' an internalcombustion engine and also with the Carburettor thereof whereby thesuction stroke of the engine creates a vacuum in the vacuum tank to drawthe liquid from the supply tank thereto and the liquid is fed by meansof gravity to the Carburettor. One end of the supply pipe 2 communicatesat 2 with the supply tank l adjacent the bottom thereof and just abovethis communication the pipe is provided with an opening 3 adapted topermit air to be drawn into the pipe when the liquid level in the supplytank falls below the opening. V

4 is an indicating device comprising a chamber having` two legs 5a and5l which communicate with one another at their lower ends, thecommunication being formed by means of a passage 6. The upper end ort'veach of these legs is suitably connected in the supply pipe line 2 sothat the liquid passing therethrough also passes into and down the inletlegs 5a, through the passage (i and then up and out the outlet leg 5l.TVith this arrangement it will be seen that when the liquid level in thesupply tank l is above the opening 3, the legs 5 and 5l will beconstantly iilledwith liquid while the engine is running. Should theengine be stopped the liquid in the said legs will be trapped and thusheld at a high level therein.

It will also be noted that when the liquid level in the supply tank l*falls below the opening` 3, air will be drawn into the pipe line 2 andthus into the inlet leg 5a of the indicating device. This will cause theliquid level therein to all below its normal height as the air. drawn inwill accumulate in the upper part ofthis chamber. i

Any suitable means may be employed to visibly indicate the Vrise andfall oit' the liquid in the leg 5a though the following arrangement ispreferable. In the inlet leg 5a of the chamber is rotatably mounted'adisk 7 to which is secured a lioat 8.' The wall oi' the chamber in frontof the disk isprovided with light transmitting openings 9 which areformed by leaving clear spaces in a painted glass iront 'l0 which issuitably secured in the wall oi' the chamber. Spots ll, of contrastingcolor to thatV painted on the glass front l0', are painted on the disk 7and these `spots are adapted `by means of the float 8 to Ithe glass'front 10 so that onlyone color will be shown when the flpat 8 is raisedby means of the liquid level rising to its normal position. To ensurethe registration ot' the spots 11 with the openings 9 and to prevent theiloat coming to rest in an inoperative position I provide'the stop 12adapted to limit the movement of the loat in either direct-ion;

The indicator 4 will be mounted on the instrument board 14 of anautomobile so that the driver can easily see the spots 11 when the'liquid vlevel in the tank 1 drops to its predetermined minimum level.It will be noted that the air inlet opening 3 is very small incomparison with the liquid inlet 2a so that a` sutlicient quantity ofyliquid' fuel will be drawn into the supply pipe 2, when the opening 3vis uncovered and the `warningl given, to enable the automobile'to bedriven a reasonable distance to obtain more tuch lVhen the tank 1 isrelilled and the engine" is again started the air inthe leg fwill bedrawn through the'pipe line 2 and the liquid level in the leg/ will Yberaisedto its vnormal position. The float 8 will then be raised to bring`the spots on the disk out of register with the light,transmittingopenings 9. To enable this to be accomplished more quickly l provideAthevbleed 15 which forms ,coin munication between the upper ends vofthelegs 5 and 5P so that theairin the former will be drawn directly intothe pipe line 2 instead of passing around the trap.

What lclainriszl, i i e 1. n liquid level indicating apparatus thecombination with a supply tank, andA a vacuum feed system includingl asupply pipe conmiunicating with the tankfadjacent the bottom thereof',of means adapted topermit air to be drawn into the said pipe when theliquidy levelyin the tank falls below a predetermined minimum; vanindicating devicelincluding a chamber' lconnected in Vsaid pipe havinganormally high liquid level; mea-ns whereby the liquid levelin thechamber falls when air is being drawn into the pipe, one wall ofthecliamber being provided with a lighttransmitting opening; a iloat inthe chamber; and an oscillating member secured to the float and providedwith a colored spot, the iloat being adapted to position the spot intoand out of register with the said light transmitting opening. y Y

2. A liquid level indicatingv device comprising a chamber lhaving twovlegs communicating at their lower ends and having their upper endsadapted to be connected intermediate theends of a supply pipe of avacuum feed systenrwhich a`lsowinclud'esp-la supplytank, thesaid pipecomnnmicating with thetank adjacent .the bottomv thereof andliaving an'Vopening above `the said comn'iunication to permit air to be drawn intothe pipe whenn the level ofthe/liquidV vin the tank tails below a pret.inined niinimuijn and meansv for giving' an Ain li'cationA when thesaid opening yis uncoveredby the liquid.

3. A liquid level indicating device coinprising a chamber having twolegs communicating at their lower ends and having their upper endsadapted to-be connected intermediate the ends of a supply pipe ot avacuum feed system which also includes a supply tank, the said pipecommunicating with the tank adjacent the bottom thereof and having anopening above the said communicationto permit air to be drawn into thepipe when the level of the liquid in the tank falls below apredetermined mininnnn, the inlet leg'of the chamber having` atransparent portion; and a iioat in the inlet leg of thechaiiiberadapted to fall Yfrom its normal position when the air isadmitted to the chamber. i

H-L. A liquidlevel indicating device comprising a Achamber having twolegs communicating at their lower ends and, having'l their upper endsadapted to be connected' in a su'pplypipe of a vacuum feed system whichalso includesr a supply tank, the said pipe communicating with the tankadjacent the bottoni thereof andhaving an opening above thesaidcommunication to permit air to be drawn into the pipe when the levelot' the liquidV in the tank falls below a predetermined minimum; a bleedbetween the upper ends lof the said two legs whereby the air in theinlet leg will` quickly exhausted therefromtoppermit the' liquid levelin the inlet leg to rise quickly when the liquid level in the tank isagain raised above the said opening, and means tor indicating the riseand i'all of the liquid in the chamber.

.` `li'qiiid level indicating device com-v prising a chamber having twolegs communieating at their lower ends and having their uppernendsadapted 'to be connected in a supply pipe of a vacuum feed system whichalso includes a supply tank, -the said pipe communicating with the tankadjacent the bottom thereof and having' an opening above the saidcommunication to permit air to be drawn into the pipe when the level ofthe liquid inthe tank falls below a predetermined mininium, the saidopening being smaller than the said communication wherebythe ,VlCuumsystem will draw air and liquid `through the legsot the chamber lwhenthe opening is uncovered and the liquid level in the inlet will be belowits normal position; and'means for indicating' tlie-.iise and fall ofthe liquid in the said inlet leg.

v '6. A liquid level indicating device eomprising a. chamber having vtwolegs coinmunicating at their lower ends and having their upper endsadapted'to b'e connected in ajsu'pply pippe of a lvacuum feed systemwhich also includespa supply tank, the said pipe communicating with thetank adjacent 4the bottom the'eof and having an opening above the lsv icommunication to permit air to be'drawninto `the pipe when the vlevel ofthe liquid in the tank falls below a predetermined minimum; and meansincluding a chamber when the opening is uncovered s0 'lout mounted inthe inlet leg of the chamber that the float will fall but liquid "wille0n for indicating the rise und fall of thel liquid tinue to flowthrough the chamber. 10 ,in the inlet leg of the chamber, the 'saidSigned ut Toronto, Canada this 19th (luy opening being Smaller than theSuid Comof September 1923;

munication whereby the Vacuum System Will draw air und liquid throughthe legs of the MAUNSELL B. JACKSON.

